Valved conduits or grafts, which are arrangements including a prosthetic vascular conduit with an associated valve to control flow of blood through the conduit, are used for various purposes including, for example, the replacement of the aortic valve in conjunction with the ascending aorta.
The aorta is the largest blood vessel in the human body, carrying blood from the left ventricle of the heart throughout the body. The ascending aorta is the first section of the aorta, which stems from the left ventricle and extends to aortic arch. The aortic valve is located at the root of the ascending aorta and controls the blood flow by permitting blood to flow from the left ventricle into the ascending aorta while preventing or restricting blood flow in the opposite direction. The coronary arteries, which supply blood to the heart muscle itself, branch from the ascending aorta. Downstream of the aortic valve, the wall of the ascending aorta exhibits three outward protrusions approximately spaced 120 degrees apart. These protrusions are known as the Valsalva sinuses. For replacement of the aortic valve and the ascending aorta, the valve in the valved conduit is arranged at one end of the prosthetic vascular conduit with its leaflets oriented to permit blood flow from the left ventricle into the conduit, while preventing blood flow out of the conduit in the opposite direction.
Practitioners may prefer having the option of coupling the valve to the conduit just before the replacement procedure. In some cases, for example, practitioners wish to couple the valve to the conduit, possibly in the operating room, only after the specific requirements (e.g., anatomy and pathology) of the patient are known.